Charging system for electric or hybrid vehicles and associated vehicles

Abstract

Charging system for electric or hybrid vehicle and associated vehicle. The present invention relates to a charging system (1) for an electric or hybrid vehicle comprising a traction battery (2), an inverter (3) and an AC motor (4), the charging system (1) comprising a voltage booster assembly (5), first connection means (11, 12) for the traction battery (2) to the input of the inverter (3) and second connection means (13, 14) for a charging socket (8) to the input of the voltage booster assembly (5), the charging system (1) being characterized in that it further comprises third connection means (14, 15) suitable for directly connecting the traction battery (2) to the charging socket (8). (Figure 1)

Description

Title of the invention: Charging system for electric or hybrid vehicles and associated vehicles

[0001] The present invention relates to the fields of automotive and electrotechnics, and more specifically concerns a charging system for electric or hybrid vehicles and a vehicle comprising such a charging system.

[0002] An electric or hybrid vehicle has a high-voltage traction battery, which discharges to power the vehicle's electric traction motor. This motor therefore requires a traction battery charging system. Such a system recharges the traction battery by recovering energy during vehicle braking, or from an external charging station. However, not all charging stations provide the same type of charge. The vehicle's charging system should therefore preferably include several types of chargers depending on the type of charge, for example, a charger dedicated to alternating current charging and a device dedicated to direct current charging using an external charger.

[0003] By addressing all these constraints, such a charging system can therefore prove to be very bulky and very expensive, especially if certain components of the charging system are not shared as much as possible. It is known, in particular, to use the stator inductances of an electric traction motor of an electric vehicle, and the associated traction inverter, to create a voltage step-up stage for a vehicle charger, as described, for example, in document FR2943188.

[0004] Similarly, in order to reduce the cost and complexity of the charging system, it is preferable to use only one charging socket to connect to a DC charging station, regardless of the voltage level that this charging station can supply. However, some vehicles now have traction batteries with a maximum open-circuit voltage much higher than the maximum voltage level available at the output of a conventional charging station, so that in such a vehicle, the DC charging socket can no longer be directly connected to the vehicle's traction battery, but must be connected to the input of a voltage booster stage which is itself connected at the output to the traction battery.

[0005] When this voltage step-up stage uses the stator inductances of an electric motor from the vehicle and an inverter from the vehicle, this means that this motor and this inverter must be sized to support the charging current of the traction battery, regardless of the voltage level supplied by the charging terminal. In other words, even if, for example, for the vehicle's driving operation, an electric motor and an inverter capable of supporting a maximum phase current of 130 A (Amperes) sufficient, the vehicle will have to integrate an electric motor and an inverter supporting a higher maximum phase current, corresponding to a charging current of the traction battery supplied by a charging terminal with a very high charging voltage, on the order of 800V (Volts) for example.

[0006] Furthermore, the systematic passage of the traction battery charging current through the voltage booster stage induces electrical losses in the components of the voltage booster stage, even when its voltage booster function is not used.

[0007] Finally, the design of such a charging system is guided by minimizing the number of controlled switches to reduce the cost of the system, its size and complexity, but also by minimizing the number of activations of these switches, to avoid their premature wear.

[0008] The present invention aims to remedy at least in part the drawbacks of the prior art by providing a charging system for an electric or hybrid vehicle, and such a vehicle, enabling the charging of a traction battery of the vehicle using a DC charging terminal, whether the voltage level supplied by the charging terminal is lower or higher than that of the traction battery, without the need for oversizing of an electric motor and inverter of the vehicle, and minimizing electrical losses during this charging.

[0009] To this end, the present invention proposes a charging system for an electric or hybrid vehicle, the vehicle comprising a traction battery, an inverter suitable for being connected at the input to the traction battery and connected at the output to an AC motor, the charging system comprising a voltage booster assembly, the charging system further comprising first means for connecting the traction battery to the input of the inverter and second means for connecting a charging socket to an input of the voltage booster assembly, the charging system being characterized in that it further comprises third means for connecting the traction battery directly to the charging socket.

[0010] By "connect directly", it is understood that the third means of connection are capable of connecting the charging socket to the terminals of the traction battery without going through the voltage booster assembly, with only a few conductors or components of zero or near-zero resistance separating the charging socket from the traction battery when the third means of connection are used.

[0011] Furthermore, in this patent application, unless otherwise stated, an input or output connection of a functional assembly such as an inverter or a voltage booster assembly is understood as a connection across the terminals of that input or output respectively, that is to say, a parallel connection to that input or output respectively. Here, the inverter is notably connected at the output (by (in relation to its inverter function) to the phase connections of the vehicle's electric motor.

[0012] In this application as well, the traction battery is understood as a battery powering the inverter and the electric motor while the vehicle is in motion, unlike a vehicle service battery that powers a low-voltage electrical system (e.g., 14V) to which various consumers, including the vehicle's main computer, are connected. The traction battery can therefore also be understood as a propulsion battery, depending on the electric motor used. Unless otherwise specified, the battery referred to in this application is the vehicle's traction battery. Similarly, the motor and inverter in this patent application refer to an electric traction or propulsion motor and a traction or propulsion inverter for the vehicle, unless otherwise indicated. Finally, the terms "charge" and "recharge" are considered equivalent in this application.

[0013] Thanks to the invention, a DC charging current for the traction battery passes through the voltage booster assembly when the first and second connection means are used, or goes directly to the traction battery when the first and third connection means are used. This latter case corresponds to charging during which the vehicle is connected to a charging station providing a charging voltage higher than the voltage at the traction battery terminals. By not passing through the voltage booster assembly, the charging current from such a charging station does not suffer electrical losses in the voltage booster assembly. This also avoids oversizing the vehicle's electric motor and inverter to accommodate such a charge (with a charging voltage higher than the battery voltage), compared to their design requirements for vehicle operation.

[0014] Preferably, the charging system comprises the inverter, the motor, and means for controlling the inverter and the motor to form the voltage boosting assembly. This saves space in the motor compartment and the cost of specific components required to build this voltage boosting assembly.

[0015] In one embodiment of the invention, in the charging system according to the invention: - The first means of connection comprise at least one first switch, called the positive battery switch, connected by one of its terminals to a positive terminal of the traction battery and by a second of its terminals to a positive input terminal of the inverter, and a second switch, called the negative battery switch, connected by one of its terminals to a negative terminal of the traction battery and by a second of its terminals to a negative input terminal of the inverter, - the second means of connection comprise, on the one hand, a first switch, called a positive DC switch, connected by one of its terminals to a positive terminal of the load socket and by a second of its terminals to a positive input terminal of the voltage booster assembly, and on the other hand, a second switch, called a negative DC switch, connected by one of its terminals to a negative terminal of the load socket and by a second of its terminals to a negative input terminal of the voltage booster assembly, and The third connection method comprises the negative DC switch and a bypass switch, connected by one of its terminals to the first or second terminal of the positive DC switch, and by a second terminal to the second terminal of the positive battery switch. Preferably, the positive input terminal of the step-up voltage assembly is connected to the first terminal of a step-up switch, which is itself connected by a second terminal to an inductor of the step-up voltage assembly. This provides a safety feature during operation, during which the step-up switch is opened, preventing current from flowing through the step-up voltage assembly. If the step-up voltage assembly consists of the inverter and the motor, the second terminal of the step-up switch is connected to a neutral point of the AC motor.Furthermore, in this case, the negative terminal of the voltage booster assembly corresponds to the negative terminal of the inverter (in the sense that they are at the same potential).

[0016] The connections described above concerning the terminals of the switches are understood as direct connections, that is to say made of components of zero or almost zero resistance having only a conductive function, except possibly having a fuse function or additional switch which is not the subject of the invention.

[0017] This embodiment minimizes the number of switches in the charging system by using the negative DC switch both for charging the traction battery through the voltage booster assembly and for charging the battery without this assembly. These switches are power switches, for example, mechanical relays or MOSFETs (Metal Oxide Semiconductor Field Effect Transistors). The first and second terminals of each switch correspond to separate terminals of that switch.

[0018] According to a preferred embodiment of this invention, the bypass switch is connected by its first terminal to the first terminal of the positive DC switch. This preferred embodiment of The invention eliminates the need to close the positive DC relay when charging the traction battery without passing through the voltage booster assembly. Furthermore, when the voltage booster assembly includes an input capacitor, this variant prevents coupling of this capacitor with a smoothing capacitor connected to the traction battery input, as such coupling could damage the charging process or the charging system.

[0019] In another embodiment of this invention, the bypass switch is connected by its first terminal to the second terminal of the positive DC switch. In this case, the positive DC switch is closed during traction battery charging that does not pass through the voltage booster assembly. This can be advantageous if there is a direct transition from traction battery charging through the voltage booster assembly to traction battery charging without the voltage booster assembly, as only one switch needs to change state during this transition.

[0020] In this embodiment of the invention, the charging system according to the invention comprises, on the one hand, means for communicating with a DC charging terminal to which the charging socket is connected, capable of determining a charging voltage delivered by the charging terminal, and on the other hand, means for controlling the first, second and third connection means, the control means being capable of closing the positive and negative battery switches as well as the positive and negative DC switches when the charging voltage determined by the communication means is less than a voltage of the traction battery, and being capable of closing the negative DC and bypass switches when the charging voltage determined by the communication means is greater than the maximum open-circuit voltage of the traction battery.Of course, if the charging voltage determined by the communication means is lower than the traction battery voltage, the bypass switch is open or held open. Similarly, if the charging voltage determined by the communication means is higher than the traction battery voltage, the positive DC switch is opened or held open in the preferred embodiment of this invention. In the other embodiment, however, the positive DC switch is held closed when the charging voltage determined by the communication means is higher than the traction battery voltage.Finally, the control systems are capable of closing the positive and negative battery switches as well as the positive and negative DC switches in the event that the charging voltage determined by the communication systems is higher than the traction battery voltage but lower than the maximum open-circuit voltage of the traction battery.

[0021] Preferably, the voltage step-up assembly further comprises a capacitor, referred to as the step-up capacitor, connected by one of its terminals to the negative input terminal of the voltage step-up assembly and by a second of its terminals to the first terminal of the step-up switch. This capacitor notably ensures the safety of the start of a load using the voltage step-up assembly.

[0022] The invention also relates to an electric or hybrid vehicle comprising the charging system according to the invention and the traction battery, characterized in that it further comprises a connection box, the connection box having a connector electrically connected to the inverter input, a connector electrically connected to the charging socket, a connector electrically connected to the traction battery, and a connector electrically connected to the positive input terminal of the voltage booster assembly, and the connection box having the positive and negative battery switches, the positive and negative DC switches, and the bypass switch. This box allows for ease of assembly and wiring.

[0023] The connection box also includes a pre-charge device, a first terminal of which is connected to the positive terminal of the battery and a second terminal is connected to the positive input terminal of the inverter.

[0024] By "electrically connected" is meant a direct connection without an intermediate switch. The junction box thus allows the main switches of the charging system (except for the step-up switch) to be grouped together and ensures electrical safety around these main switches, particularly when they are mechanical relays. The junction box also facilitates the maintenance of these main switches.

[0025] In one embodiment of the invention, the electric or hybrid vehicle according to the invention further comprises a smoothing capacitor connected to the output of the voltage booster assembly. This smoothing capacitor is therefore connected to the input of the inverter; it serves to smooth the current arriving in the traction battery when the inverter operates as a rectifier during regenerative braking, or when the voltage booster assembly operates as a voltage booster.

[0026] According to an advantageous feature of the electric or hybrid vehicle according to the invention, it includes means for detecting when the bypass switch becomes stuck after the traction battery has been charged using the bypass switch. This detection makes it possible to prevent charging the traction battery using a terminal with a voltage level lower than that of the traction battery, until the switch is replaced. "Stuck" means that the switch is held welded at its terminals if it is a mechanical relay, or that the switch is damaged and constantly held in this state. passing if it is a MOSFET transistor.

[0027] Advantageously, the electric or hybrid vehicle according to the invention includes means for monitoring the traction battery voltage and current, the control means being capable of opening the positive and negative battery switches and / or the positive and negative DC switches and / or the bypass switch when the control means detect an anomaly. This anomaly is, for example, an excessively rapid rise in the battery voltage or in the voltage of a portion of the battery cells.

[0028] Other features and advantages of the invention will become apparent from the following description on the one hand, and from several illustrative and non-limiting examples of embodiments given with reference to the accompanying schematic drawings on the other hand, in which:

[0029] [Fig. 1] illustrates a charging system for a traction battery of an electric or hybrid vehicle according to the invention, in one embodiment of the invention,

[0030] [Fig. 2] illustrates the position of switches of the charging system of the [Fig. 1] in vehicle driving situation,

[0031] [Fig.3] illustrates the position of these switches during battery charging. traction with a charging station capable of supplying a maximum voltage lower than the maximum open-circuit voltage of the traction battery, and

[0032] [Fig.4] illustrates the position of these switches during battery charging. traction with a charging station capable of supplying a maximum charging voltage higher than the maximum open-circuit voltage of the traction battery.

[0033] According to an embodiment of the invention illustrated [Fig. 1], an electric or hybrid vehicle according to the invention comprises a charging system 1 according to the invention, enabling the recharging of a traction battery 2 of the vehicle. The vehicle comprises a traction inverter 3 and a three-phase electric motor 4 connected to the wheels of the vehicle by a drive chain, the inverter 3 and the motor 4 being powered by the traction battery 2 to propel the vehicle.

[0034] The vehicle includes, for this purpose, to connect the traction battery 2 to the inverter 3, a first switch 11, called the positive battery switch, connected by one of its terminals to a positive terminal of the traction battery 2 and by a second of its terminals to a positive input terminal of the inverter 3, and a second switch 12, called the negative battery switch 12, connected by one of its terminals to a negative terminal of the traction battery 2 and by a second of its terminals to a negative input terminal of the inverter 3. The inverter input is understood here as the part of the inverter that receives a direct current and transmits a rectified current; that is to say, the input is understood in relation to the inverter function. Similarly, in this application, the terms "input" or "output" are understood as related to the function of the electrical component or assembly being considered. A smoothing capacitor 7 is connected to the input of the inverter. It smooths the current entering the battery 2 when the inverter 3 is used as a rectifier at the output of the electric motor 4 operating in generator mode.

[0035] The positive battery switches 11 and negative 12 therefore constitute the first means of connecting the traction battery 2 with the input of the inverter 3. The inverter 3 is also directly connected at the output to the electric motor 4, i.e. without an intermediate switch.

[0036] The vehicle also includes a DC-DC converter 30 connected to the terminals of the smoothing capacitor 7, enabling the charging of a service battery 31, intended to power vehicle consumers (lighting system, etc.). The vehicle also includes a charger 32 capable of charging the traction battery 2 using an AC charging terminal. The charger 32 is connected at its output to the terminals of the smoothing capacitor 7 and at its input to a charging socket 33 dedicated to AC charging. This charging socket 33 is, for example, a type 2 connector conforming to IEC 62196 (International Electrotechnical Commission standards set).

[0037] The vehicle also includes a charging socket 8 intended to be connected to a DC charging station. This charging socket 8 is, for example, a CHAdeMO connector conforming to IEC 61851-23, -24. Alternatively, the vehicle has only one charging socket that can be connected to both a DC charging station and an AC charging station, for example, a Combo DC charging socket conforming to IEC 62196-3. In yet another variant, the vehicle has only one charging socket intended exclusively for connection to a DC charging station.

[0038] The charging system 1 includes control means 40 for the inverter 3 and the motor 4 to use the assembly 5 of the inverter 3 and the motor 4 as a voltage boost stage, when charging the traction battery 2 using a charging voltage supplied by a charging terminal lower than the maximum open-circuit voltage of the traction battery 2. In this case, the stator inductances of the electric motor 4 are used as current storage inductances in the voltage boost assembly 5, these stator inductances discharging into the traction battery 2 through the inverter 3 according to a duty cycle of the switching switches of the inverter 3, fixed by the control means 40, comprising a voltmeter U across the terminals of the boost capacitor 6.

[0039] A negative terminal of the elevator capacitor 6 is connected to the negative input terminal of the inverter, and a positive terminal of the elevator capacitor 6 is connected to the neutral point of the electric motor 4 via a switch 16. This switch 16, also called a step-up switch, is connected by one of its terminals to the positive terminal of the capacitor in the lift 6 and by the other terminal to the neutral point of the electric motor 4. This step-up switch 16 allows the capacitor in the lift 6 to be disconnected from the input of the voltage booster assembly 5 outside of the charging phases of the traction battery 2 via an external charging terminal. Specifically, this step-up switch 16 is open when the vehicle is in motion. Thus, while the vehicle is in motion, capacitive coupling of the capacitor in the lift 6 with the electric motor 4 is prevented.

[0040] The control means 40 of the inverter 3 are, for example, a microcontroller controlling the switches of the inverter 3, both in traction mode and in vehicle charging mode, when this charging mode uses the elevator function of the assembly 5.

[0041] Second vehicle connection means allow the DC charging socket 8 to be connected to the input of the voltage booster assembly 5. These second connection means comprise: - a switch 13, called a positive DC switch, connected by one of its terminals to a positive terminal of the charging socket 8 and by a second of its terminals to the step-up switch 16, and - a switch 14, called a negative direct current switch, connected by one of its terminals to a negative terminal of the load socket 8 and by a second of its terminals to the negative input terminal of the inverter 3.

[0042] These second means of connection are used to recharge the traction battery 2 via the voltage booster assembly 5 when a charging voltage of a charging terminal to which the charging plug 8 is connected is less than the maximum open-circuit voltage of the battery 2.

[0043] Finally, third means of connecting the vehicle allow the DC charging socket 8 to be directly connected to the traction battery 2, and are used to recharge the latter when a charging voltage of a charging terminal to which the charging socket 8 is connected is greater than the voltage across the terminals of the battery 2. The third means of connecting comprise the negative DC switch 14 and a switch 15, called the bypass switch, connected by one of its terminals to the first terminal of the positive DC switch 13, and by a second of its terminals to the second terminal of the positive battery switch 11. Alternatively, the bypass switch 15 is connected by its first of its terminals to the second terminal of the positive DC switch 13, and by its second of its terminals to the second terminal of the positive battery switch 11.

[0044] The switches 11, 12, 13, 14, and 15 are mechanical relays, grouped in a junction box 9 of the charging system 1. The junction box also includes a pre-charge relay 10 connected by one of its terminals to the positive terminal of the traction battery 2 and by the other terminal to the positive terminal of the inverter 3. A pre-charge resistor is connected between the pre-charge relay 10 and the positive terminal of battery 2. Before charging battery 2, the pre-charge relay 10 is first closed to charge the smoothing capacitor 7, then the pre-charge relay 10 is opened, and the positive battery relay 11 is closed. The pre-charge relay 10 and the pre-charge resistor form a pre-charge device. It should be noted that other types of pre-charge devices can be used instead of such a relay and resistor system.

[0045] The electrical outputs of the connection box 9 are made via electrical connectors 17, 18, 19 and 21. Connector 18 is electrically connected to the input of the inverter 3, connector 17 is electrically connected to the charging socket 8, connector 21 is electrically connected to the traction battery 2 and connector 19 is electrically connected to the positive terminal of the elevator capacitor 6.

[0046] In this embodiment of the invention, the charging system 1 comprises the voltage booster assembly 5, the charger 32, the charging sockets 8 and 33, and the connection box 9. It also comprises one or more software and / or hardware modules of a main control unit 50 of the vehicle. In particular, the main control unit 50 includes means for communicating with a charging station 60 or 70 (referenced in Figures 3 and 4), which are part of the charging system 1.

[0047] The charging system 1 also includes means for controlling, on the one hand, the second and third connection means and, on the other hand, the lift switch 16, these control means being present in the main computer 50 of the vehicle.

[0048] The charging system 1 also includes means for controlling the pre-charge relay 10 and the positive battery switches 11 and negative battery switches 12, these control means also being present in a traction battery management system 20, which may form an integral part of the charging system 1. The battery management system 20 is coupled to a sensor 22 for a current entering the battery 2 (this sensor 22 being connected to the ammeter A in [Fig. 1]) and a charging voltage supplied by the charging terminal 60, 70 (this sensor 22 being connected to the voltmeter V in [Fig. 1]), which allows it to monitor the charging of the battery 2. The battery management system 20 also includes means for controlling the bypass switch 15 and the positive DC switches 13 and negative DC switches 14.Thus, when the battery management system 20 detects a fault during charging, it can interrupt it for safety without intervention from the cal. The main control unit 50 of the vehicle. Switches 10, 11, 12, 13, 14, and 15 are therefore each controllable by the management system 20 and by the main control unit 50 of the vehicle, thus providing safety redundancy. Similarly, the lift switch 16 is controllable by the main control unit 50 and by the control means 40.

[0049] To further enhance the safety of the charging system 1, the main control unit 50 detects a potential sticking of one of the switches 10, 11, 12, 13, 14, 15, or 16 used during traction battery charging, at the end of that charging cycle, and imposes a degraded operating mode on the vehicle if such a sticking is detected. This detection uses, for example, voltage measurements at various points in the charging system 1.

[0050] The operation of the charging system 1 is now explained in relation to different vehicle use cases, in which the maximum open-circuit voltage of the traction battery is 800V. Of course, the invention is usable with batteries having different maximum open-circuit voltages.

[0051] During vehicle operation, as shown in [Fig. 2], the positive DC switches 13 and negative DC switches 14, the bypass switch 15, the pre-charge relay 10, and the lift switch 16 are held open by the charging system 1, while the positive battery switches 11 and negative battery switches 12 are held closed. Thus, the traction battery 2 powers the inverter 3 and the electric motor 4, which provides propulsion or traction for the vehicle. It should be noted that in this situation, the bypass switch 15 could be held closed, for example, to limit its number of activations or due to a fault in this switch, without impairing the vehicle's operation while in operation. Conversely, in the embodiment where the bypass switch 15 is connected by one of its terminals directly to the positive terminal of the lift capacitor 6 (i.e.(without the positive DC switch between these two components), closing this switch would induce coupling of the elevator capacitor 6 with the electric motor 4, which would be detrimental.

[0052] Figure 3 illustrates a charging situation for the traction battery 2 using the charging terminal 60, which does not deliver a voltage level exceeding the battery's maximum open-circuit voltage. For example, this charging terminal can provide a maximum charging voltage of 400V or 500V. In this application of the invention, it is assumed that the voltage across the terminals of the battery 2 is higher than the maximum charging voltage delivered by the charging terminal 60. The computer 50 was able to determine this maximum charging voltage and the fact that it was lower than the maximum open-circuit voltage of the battery 2 before charging the battery 2 by communicating with the charging terminal 60. During this charging process, the charging system 1 keeps the boost switch 16 and the positive DC switches closed. 13 and negative 14, as well as the positive battery switches 11 and negative 12. On the other hand, the charging system 1 keeps the bypass switch 15 open. It should be noted that during this charging, the pre-charge relay 10, managed by the management system 20, is also left open (with the exception of the pre-charge period preceding this charging of the traction battery 2, in which the pre-charge relay 10 is closed and the positive battery relay 11 is open).

[0053] In this situation, the charging voltage applied by the charging terminal 60 is applied to the capacity of the booster 6, and the control means 40 of the inverter control the voltage booster assembly 5 to provide at the output of this voltage booster assembly 5 (therefore at the input of the inverter), a voltage greater than the voltage of the battery 2.

[0054] Figure 4 illustrates a charging situation for the traction battery 2 using the charging terminal 70, which delivers a voltage level of up to 820V. The main computer 50, having communicated with the charging terminal 70, requested a charging voltage higher than the voltage of the battery 2, which is itself less than 800V (since it needs to be recharged). During the charging of the traction battery 2 with this charging terminal 70, the charging system 1 keeps the boost switch 16 and the positive DC switch 13 open. During this charging, the pre-charge relay 10 is kept open (except for the pre-charge period preceding this charging of the traction battery 2, in which the pre-charge relay 10 is closed and the positive battery relay 11 is open). On the other hand, it keeps closed the negative current switch 14, the bypass relay 15 as well as the positive battery switches 11 and negative battery switches 12.

[0055] In this situation, the charging voltage delivered by the charging terminal 70 is directly applied to the terminals of the traction battery 2, without any electrical loss generated by the inverter 3 or the electric motor 4, nor any undesirable capacitive effect. It should be noted that, conversely, in the embodiment where the bypass switch 15 is connected by one of its terminals directly to the positive terminal of the lift capacitor 6, there is coupling of the lift capacitor 6 with the smoothing capacitor 7, which is detrimental to the charging of the battery 2. Furthermore, in this embodiment, the positive DC switch 13 is kept closed during this charging process.

[0056] Of course, the invention is not limited to the examples just described and many modifications can be made to these examples without departing from the scope of the invention.

Claims

1. Claims Charging system (1) for an electric or hybrid vehicle, the vehicle comprising a traction battery (2), an inverter (3) capable of being connected at the input to the traction battery (2) and connected at the output to an alternating current motor (4), the charging system (1) comprising a voltage booster assembly (5), the charging system (1) further comprising first means (11, 12) for connecting the traction battery (2) to the input of the inverter (3), second means (13, 14) for connecting a charging socket (8) to an input of the voltage booster assembly (5), and third connection means (14, 15) capable of directly connecting the traction battery (2) to the charging socket (8), - the first connection means (11, 12) comprising at least a first switch (11), called the positive battery switch, connected by a first of its terminals to a positive terminal of the traction battery (2) and by a second of its terminals to a positive input terminal of the inverter (3), and a second switch (12), called the negative battery switch, connected by a first of its terminals to a negative terminal of the traction battery (2) and by a second of its terminals to a negative input terminal of the inverter (3), - the second connection means (13, 14) comprising on the one hand a first switch (13), called a positive direct current switch, connected by a first of its terminals to a positive terminal of the charging socket (8) and by a second of its terminals to a positive input terminal of the voltage booster assembly (5), and on the other hand a second switch (14), called a negative direct current switch, connected by a first of its terminals to a negative terminal of the charging socket (8) and by a second of its terminals to a negative input terminal of the voltage booster assembly (5), - the third connection means (14, 15) comprising the negative direct current switch (14) and a switch (15), called a bypass switch, connected by a first of its terminals to the first terminal of the positive direct current switch (13), and by a second of its terminals to the second terminal of the positive battery switch (11), the charging system (1) being characterized in that the voltage booster assembly (5) further comprises a capacitor (6), called the capacitor the booster, connected by a first of its terminals to the negative input terminal of the voltage booster assembly (5) and by a second of its terminals to the first terminal of a switch (16), called a booster switch, the first terminal of the booster switch (16) being further connected to the positive input terminal of the voltage booster assembly (5), and the second terminal of the booster switch (16) being connected to an inductance of the voltage booster assembly (5).

2. Charging system (1) according to claim 1, comprising the inverter (3), the motor (4) and control means (40) of the inverter (3) and the motor (4) to form the voltage booster assembly (5).

3. Charging system (1) according to claim 1 or 2 comprising on the one hand communication means (50) with a direct current charging terminal (60, 70) to which the charging socket (8) is connected, capable of determining a charging voltage delivered by the charging terminal (60, 70), and on the other hand means for controlling the first, second and third connection means, the control means being capable of closing the positive (11) and negative (12) battery switches as well as the positive (13) and negative (14) direct current switches when the charging voltage determined by the communication means (50) is lower than a voltage of the traction battery (2), and being capable of closing the negative (14) direct current and bypass (15) switches when the charging voltage determined by the communication means (50) is higher than the maximum no-load voltage of the traction battery (2).

4. Electric or hybrid vehicle comprising a charging system (1) according to any one of claims 1 to 3 and the traction battery (2), characterized in that it further comprises a connection box (9), the connection box (9) comprising a connector (18) electrically connected to the input of the inverter (3), a connector (17) electrically connected to the charging socket (8), a connector (21) electrically connected to the traction battery (2) and a connector (19) electrically connected to the positive input terminal of the voltage booster assembly (5), and in which the connection box (9) comprises the positive (11) and negative (12) battery switches, the positive (13) and negative (14) direct current switches and the bypass switch (15).

5. Electric or hybrid vehicle according to claim 4, comprising means (50) for detecting sticking of the switch of bypass (15) after charging the traction battery (2) using the bypass switch (15).

6. Electric or hybrid vehicle according to claim 4 or 5, comprising means (20, 50) for controlling a voltage of the traction battery (2) and a current of the traction battery (2), the control means (20, 50) being capable of opening the positive (11) and negative (12) battery switches and / or the positive (13) and negative (14) direct current switches and / or the bypass switch (15) when the control means (20, 50, 40) detect an anomaly.

Images